Was it to early to test? should I tale another?

period started the 1st of june had unproteced sex ( pull out) one slip up around the 18th... I have had alot of strange symptoms. im dizzy, light headed all the time, have nausea no matter what I do. have been crampy for the past wk and a half but not really pms crampy boobs arent sore but are a little tender sometimes. took a test with first morning urine today with a dollar store test, and it was neg. was it to soon to test or is probably my result (-)?.. Should I retest?